1. Field of the Invention
The invention relates to a method for transmitting data in a WLAN network, a corresponding device for transmitting such data, and a corresponding data network.
2. Description of the Related Art
The transmission of data via wireless local area networks (WLANs) has become more and more widely established over the last several years. WLAN stands for “Wireless Local Area Network” and denotes a local wireless network with ranges of several hundred meters. Nowadays, users of terminal devices, in particular of mobile radio devices and laptops, have the opportunity to-register at any locations in commercially operated WLAN networks. With this arrangement the user can locate a plurality of WLAN networks via his or her terminal device, each WLAN network comprising what are known as access nodes (usually referred to as “access points”) via which the user can obtain access to further data networks, in particular to the internet or to UMTS networks.
A variety of methods for authenticating a user at the access node of a WLAN network are known from the prior art. In the WLAN standard IEEE 802.1x, for example, the EAP protocol (EAP=Extensible Authentication Protocol, see document [1]) known from the PPP environment (PPP=Point-to-Point Protocol) is used. Authentication mechanisms already known from the prior art, for example USIM or AKA, are in turn used in the EAP protocol.
A disadvantage that reveals itself in the case of the authentication mechanisms used in the WLAN environment is that the said mechanisms are not very flexible and with them it is essentially only possible to transmit authentication data without more extensive information.
The object of the invention is therefore to provide a method for transmitting data in a WLAN network which provides an improved authentication in further data networks that are connected to the WLAN network.
This object is achieved by the claims.